Cessna 421C N48DL accident

Probable cause

Pilot incapacitation, which resulted in the pilot’s inability to maintain airplane control and the airplane’s subsequent ocean impact.

NTSB analysis

According to a statement provided by the Jacksonville Center air traffic control (ATC) facility, the pilot contacted ATC while at flight level 270. About 25 minutes later, the airplane began to deviate from the ATC-assigned altitude and route. The controller’s attempts to contact the pilot were unsuccessful. The North American Aerospace Defense Command launched military fighter aircraft to intercept the airplane. The military pilots reported that the airplane was circling in a left turn at a high altitude and low airspeed and that its windows were partially frosted over. They also reported that the pilot was slumped over in the cockpit and not moving. They fired flares, and the pilot continued to be unresponsive. The airplane circled for about 3 hours before it descended into the Gulf of Mexico and sank. The pilot and airplane were not recovered. Review of the pilot’s Federal Aviation Administration medical records did not reveal any recent medical conditions that would have deemed him unfit to fly.

Text from the NTSB. Open the NTSB docket for ERA12LA290 for the full record.